Segmented current-steering digital-to-analog converter

Abstract

The invention discloses a high-speed high-accuracy digital-to-analog conversion circuit. The circuit comprises a reference voltage generation circuit, a reference voltage-to-reference current conversion circuit, a coding circuit, a current source matrix and a switch array, wherein the coding circuit has a two-stage water-flowing type coding structure, a switch driving circuit array is connected between the two-stage water-flowing type coding circuit and the switch array, and a two-stage clock delay circuit is connected between a clock input signal and the two-stage coding circuit and provides a clock signal to the two-stage water-flowing type coding circuit; and the current source matrix, a current switch and the coding circuit have a '5+4+5' segmental structure, namely high 5 bits and middle 4 bits have a thermometer code structure, and low 5 bits have a binary code structure. The high-speed high-accuracy digital-to-analog conversion circuit effectively reduces the area and the power consumption of chips, reduces the complexity of the coding circuit, increases conversion rate, reduces burrs, and improves the dynamic characteristics of a digital-to-analog converter. The high-speed high-accuracy digital-to-analog conversion circuit is used for digital processing systems, audio / video conversion systems and communication systems.

Description

technical field [0001] The invention belongs to the field of microelectronics, in particular to a segmented current steering digital-to-analog converter for communication and high-speed signal processing systems. Background technique [0002] A digital-to-analog converter (DAC) is considered as one of the general-purpose mixed-signal integrated circuits and has a wide range of applications in digital systems. The rapid development of digital processing technology has put forward higher requirements for digital-to-analog converters. For example, higher speed, higher precision, lower power consumption and operating voltage and so on. Digital-to-analog converters (DACs) are widely used in communication systems and audio and video processing systems. With the compatibility of integrated circuits and manufacturing processes, high-speed and high-precision digital-to-analog converters have become a hot spot in the research of analog integrated circuits. Because of its high speed...

AI Technical Summary

Problems solved by technology

[0005] This digital-to-analog converter circuit uses a thermometer pattern for the upper 6 bits, a temperature pattern for the middle 4 bits, a binary pattern for the lower 4 bits, and a temperature pattern for the upper 6 bits and the middle 4 bits, making the decoding circuit more complicated. The delay is large and the output signal is not easy to synchronize, and it consumes a large area; at the same time, since the upper 6-bit switch array contains 63 current switches composed of two PMOSs and 63 current sources, the middle 4-bit switch array contains 15 There are three current switches and 15 current sources, which consume a lot of area and power consumption; in addition, because the synchronous latch of this converter has a very small cross point adjustable range, the output signal swing is relatively large; The decoding circuit and layout layout of this structure will cause a long delay in the decoding output signal, which may cause errors in the complementary output of the synchronous latch. In severe cases, the two complementary signals will be 1 at the same time, and the differential switches will be turned off. , causing glitches, reducing the dynamic characteristics of the digital-to-analog converter, such as the signal-to-noise ratio and the dynamic range without clutter

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